Previous GeneCards Identifiers for PDHX Gene

Summaries for PDHX Gene

Entrez Gene Summary for PDHX Gene

The pyruvate dehydrogenase (PDH) complex is located in the mitochondrial matrix and catalyzes the conversion of pyruvate to acetyl coenzyme A. The PDH complex thereby links glycolysis to Krebs cycle. The PDH complex contains three catalytic subunits, E1, E2, and E3, two regulatory subunits, E1 kinase and E1 phosphatase, and a non-catalytic subunit, E3 binding protein (E3BP). This gene encodes the E3 binding protein subunit; also known as component X of the pyruvate dehydrogenase complex. This protein tethers E3 dimers to the E2 core of the PDH complex. Defects in this gene are a cause of pyruvate dehydrogenase deficiency which results in neurological dysfunction and lactic acidosis in infancy and early childhood. This protein is also a minor antigen for antimitochondrial antibodies. These autoantibodies are present in nearly 95% of patients with the autoimmune liver disease primary biliary cirrhosis (PBC). In PBC, activated T lymphocytes attack and destroy epithelial cells in the bile duct where this protein is abnormally distributed and overexpressed. PBC eventually leads to cirrhosis and liver failure. Alternative splicing results in multiple transcript variants encoding distinct isoforms.[provided by RefSeq, Oct 2009]

UniProtKB/Swiss-Prot for PDHX Gene

Required for anchoring dihydrolipoamide dehydrogenase (E3) to the dihydrolipoamide transacetylase (E2) core of the pyruvate dehydrogenase complexes of eukaryotes. This specific binding is essential for a functional PDH complex

Protein details for PDHX Gene (UniProtKB/Swiss-Prot)

Protein attributes for PDHX Gene

Size:

501 amino acids

Molecular mass:

54122 Da

Quaternary structure:

Part of the inner core of the multimeric pyruvate dehydrogenase complex that is composed of about 48 DLAT and 12 PDHX molecules. This core binds multiple copies of pyruvate dehydrogenase (E1), dihydrolipoamide acetyltransferase (DLAT, E2) and lipoamide dehydrogenase (DLD, E3).

Graphical View of Domain Structure for InterPro Entry

UniProtKB/Swiss-Prot:

No data available for
Gene Families
for PDHX Gene

Function for PDHX Gene

Molecular function for PDHX Gene

UniProtKB/Swiss-Prot Function: Required for anchoring dihydrolipoamide dehydrogenase (E3) to the dihydrolipoamide transacetylase (E2) core of the pyruvate dehydrogenase complexes of eukaryotes. This specific binding is essential for a functional PDH complex

UniProtKB/Swiss-Prot

Pyruvate dehydrogenase E3-binding protein deficiency (PDHXD) [MIM:245349]: A metabolic disorder characterized by decreased activity of the pyruvate dehydrogenase complex without observable reduction in the activities of enzymes E1, E2, or E3. Clinical features include hypotonia and psychomotor retardation. {ECO:0000269 PubMed:9399911}. Note=The disease is caused by mutations affecting the gene represented in this entry.

Publications for PDHX Gene

Organization of the cores of the mammalian pyruvate dehydrogenase complex formed by E2 and E2 plus the E3-binding protein and their capacities to bind the E1 and E3 components.(PMID: 14638692)Hiromasa Y. … Roche T.E.(J. Biol. Chem. 2004)3423